Recently, the senior population is rapidly increasing as the human lifespan extends due to improvement of a dietary life and development of a medical technology. The senior citizens have functional differences compared to the young people due to the aging of body functions. The functional differences include delayed body response time, a decreased cognitive function, and reduced equilibrium sensation. For this reason, the walking of the senior citizens becomes limited in terms of a speed, a step length, walking frequency, a behavior range and angular velocity of a joint, equilibrium sensation and the like.
Abnormal walking of the senior citizens is a major obstacle to activities of daily living (ADL), which leads to passive social participation. Therefore, in order to improve the quality of life (QOL) of the senior citizens, it is necessary to rehabilitate the walking of the senior citizens.
In order to recover the walking function of the senior citizens, it is necessary to maintain and increase the muscular strength through the systematic and repetitive rehabilitation exercise. In other words, it is important for the senior citizens to exercise regularly every day to maintain a healthy life for the rest of their life. In the case of the senior citizens with free of behavior, they may regularly perform light exercise by going to a nearby mineral spring at dawn every day or walking around the county. However, if a person has a difficulty in behavior due to the high age or disease, it is dangerous and difficult to exercise outdoors.
In addition, for rehabilitation patients who may not easily move their bodies due to various industrial accidents, traffic accidents, or diseases such as strokes, the best way to get back to a previous healthy body is to regularly perform rehabilitation exercise for a fixed time every day even at home. A robot-type walking exercise device that allows upright walking exercise by fixing the body has been released, but the device is expensive, so that it is difficult to be purchased. In addition, an exercise device that enables the senior and infirm citizens or the rehabilitation patient to easily fix the body so as to safely perform walking and running exercise is required.
This training can be performed by using robots. The robots may easily implement repetitive motions and may support the posture of the trainees, so that safety can be assured and high training effects can be expected. In reality, there are an increasing number of effective cases of rehabilitation using robots in nerve rehabilitation treatment, so that rehabilitation medical community has shown much attention in treatment using robots.
In other words, the muscular strength has to be maintained and increased through exercise in order to recover the walking function of the senior citizens. To this end, it is necessary to understand the walking characteristics of the person to organize an appropriate rehabilitation program, and to perform systematic and repetitive rehabilitation training through the rehabilitation program. In order to perform the rehabilitation training, many assistive devices are used to support the senior citizens. The assistive devices may easily implement repetitive motions and may support the posture of the patient, so that safety can be enhanced and training effectiveness can be improved. In reality, there are an increasing number of effective cases of rehabilitation using the assistive devices in upper arm rehabilitation treatment and nerve rehabilitation treatment, so that the rehabilitation medical community has shown much attention in treatment using the assistive devices.
Walking rehabilitation using robots is classified into two types. The first is a treadmill-based rehabilitation training robot for patients who are unable to stand alone, for example, ‘Locomat’ of Hocoma. The second is a knee brace for patients who are able to stand alone, but need walking training. The knee brace is classified into a manual type and a motorized type using a robot technology. An example of the motorized type is ‘BIONIC LEG’ of AlterG.
The walking rehabilitation devices utilizing the robot technology collect and analyze the walking condition of the trainee from the sensors to improve the effectiveness of the rehabilitation training. The collected and analyzed items include a walking speed, a walking pattern, shift of a center of pressure (CoP), a knee angle, an ankle angle and the like. Among the above items, measuring the center of pressure (CoP) is more important than other items. The reason is that the walking pattern and the angles of the knee and ankle are changed according to the center of pressure.
Currently, as sensors for measuring the center of pressure (CoP), a plurality of strain gauges, multi-axis load cells, and pneumatic tubes are used.
In other words, there are a method of estimating the point of the center of gravity with the highest pressure direction by comparing pressure values applied to the respective axes by using the multi-axis load cells, a method of estimating the point of the center of gravity with the highest output value change zone after dividing a sole region into zones and attaching a plurality of strain gauges, and a method of performing estimation by using the pneumatic tubes and a plurality of force sensing registers (FSR) similarly to the method using the strain gauges.
One example of the above-described technology is disclosed in the following documents and the like.
For example, as shown in FIG. 1, Korean Patent Registration No. 10-0651639 (registered on Nov. 23, 2006) discloses an air tube 12 and a footplate 16 on which the air tube 12 is seated, a silicon pad 14 and the like, in which the air tube 12 has a concentric structure which is rolled several times, the footplate 16 is formed at front and rear sides thereof with a mounting hole 20 on which the air tube 12 is seated, the silicon pad 14 includes an upper silicon pad 14a and a lower silicon pad 14b respectively attached to a top surface and a bottom surface of the footplate 16 on which the air tube 12 is seated, a discharge tube 18 of the air tube 12 is connected to a pneumatic sensor attached to a calf operation device connected to an upper side of an ankle and sole operation device, the pressure change of the air tube 12 is detected while the pressure change is received in the unit of voltage, and an output end of the pneumatic sensor of a sole pressure sensor 10 is wire-connected to a control computer 108 embedded in a caster walker of an intelligent muscle force and walking assistive robot in such a manner that the output end may communicate with the control computer 108.
In addition, Korean Patent Registration No. 10-1246874 (registered on Mar. 18, 2013) discloses an exercise apparatus for measuring left/right side exercise information of a user body, in which a load cell including at least one strain gauge of which the length is changed by a driving force is provided, the load cell includes a driving force receiving part to which the driving force is directly applied and a curved part curved by the driving force receiving part, an exercise information generation unit calculates the driving force by using a voltage generated at both ends of the strain gauge, a position detection unit includes at least one detection point having predetermined positional relation with a position of the driving force receiving part and at least one sensor for detecting the detection point, and as the driving force receiving part is driven, one of the detection point and the sensor is driven, in which the detection point is formed on a rotary body rotated by the driving force receiving part and the sensor is fixed regardless of the rotation of the rotary body.
In addition, Korean Patent Registration No. 10-1138012 (registered on Apr. 12, 2012) discloses an apparatus for measuring the balance of a user at plural measurement postures including a pair of footplates adjusted in at least one of a vertical position, a horizontal position, and a slope according to the measurement postures and corresponding to left and right feet of the user, respectively, at least one sensor installed on the footplates for measuring a load applied to the footplates by the left and right feet of the user, and a central control unit for analyzing output signals of the sensors to measure the balance of the user for each measurement posture and generating health information of the user by using the balance for each measurement posture.
In addition, there are an increasing number of effective cases of rehabilitation using the robots in the upper arm rehabilitation treatment and the nerve rehabilitation treatment, so that the rehabilitation medical community has shown much attention in the treatment using the robots. For example, ‘J. Perry and J. Bumfield, Gait Analysis: Normal and Pathological Function, 2nd Edition, SLACK Incorporated, 2010’ discloses a technology for designing a controller to operate according to the walking of the user as the walking rehabilitation using the robots.